Omsk was founded in 1716 as a fortress on the Om' and Irtysh river crosssings to defend eastern borders of the Russian Empire from nomadic asian tribes. The fortress of Omsk became a city in 1782. In 1822 Omsk became an administrative center of Western Siberia with authority over Tomsk, Tobolsk and Semipalatinsk provinces. Construction of the Trans-Siberian Railroad in 1896 spurred active development and industrialization of the city.
During the Civil Was after October Revolution, Omsk was the center of White (Tsarist) opposition, and in 1918 admiral Kolchak named Omsk a White Capital of Russia.
During WWII, many industrial enterprises were evacuated to Omsk from western regions of Russia and Ukraine, and the city turned into a large defense industry center. Since 1950s Omsk has the largest in Russia and second largest in the world oil refinery plant and many other enterprises connected with oil refinery products. By 1977 Omsk surpassed the 1,000,000 population mark.
Today Omsk remains the industrial center of Siberia while being one of the greenest and most comfortable cities in Russia, enhanced by its unique archtecture. In 2005 the city experienced the beginning of non-manufacturing business boom, which still continues today.